The Westport Times. TUESDAY, MARCH 15, 1870.

Westport Times, Volume IV, Issue 632, 15 March 1870, Page 2

The Westport Times. TUESDAY, MARCH 15, 1870.

While wire tramways, traction engines, and road steamers are being introduced into the colony, and warmly discussed as to their relative merits iu annihilating distance in a new country such as this, a discovery of a simple character has been made in Canterbury calculated to bo of extraordinary service in establishing and extending facilities for overland communication. We refer to the results of an experiment which has been made by Mr William White, the contractor for the construction of a bridge over that most uubridgable of rivers, the llakaia. These results point to the experiment of bridge-building eminently adapted to many situations on the West Coast. As adjuncts to horse-tracks, which are tho prominent feature of internal communication in these parts, bridges buile upon this system would, iudeed, be of inestimable service. TheTotara, Pox's River, and other streams whose names are familiar as sources of delay and danger to the traveller need no longer be so if this new system of bridging bo adopted ; the coastal and internal communication of the countrymay be perfected to a degree otherwise unattainable ; and even the bridging of such rivers as the 13idler and the Grrey, for mere horse or passenger traffic, may be contemplated with far fewer misgivings as to the possibility of its achievement than may now exist in tho minds of engineers whose " enterprises of pith and moment are turned awry" by the smallness of our Provincial exchequer. It is in the hope that the attention of the public and the Government will be warmly given to the subject that we thus prominently refer to it, believing it to be at least worthy of discussion. The Lyttelton Times has considered it worthy of \ cry pointed notice, with a similar object, and for the particulars of Mr White's plans, if plans they may be called, we cannot do better than refer to its columns. Our contemporary says:—■ " It appears that Mr White, in casting about for means to secure the scaffolding necessary for driving the piles of the bridge he has contracted to build over the Eakaia, hit upon an expedient which bids fair to prove the model of a safe and inexpensive form

of bridge for rapid shingle-bed rivers. Mr "White is not an engineer ; we have his repeated assertions to that effect; if he is, it is only in an interloping sort of way. He is, however, a very disagreeable kind of a person, who has before, in his blundering amateur stylo, violated all professional rules, maxims, and traditions, made and provided in that behalf. And, though others have proved that isolated gas pipes will resist the torrents of our mountain streams, it has been left to him to show that they will do this and support a bridge at the same time. To secure the scaffolding for pile-driv-ing, Mr White hit upon the plau of driving tubes, such as are now so extensively used about Christchurch in artesian wells—gas-piping in fact—and, finding it succeed well, the idea grew; so, extending his operations, he inserted them as piles from bank to bank, built upon them, and the result is a bridge light, but strong, and which may be cheaply and expeditiously strengthened, so as to bear any weight ever likely to tost it. A tramway is already laid upon which there is ample rootn for foot traffic.

" There is nothing in its appearance or construction to distinguish it from an ordinary very light tressel bridge, excepting the tubes, which are 16 feet long and 2J inches in diameter, driven

from 0 to 10 feet into the ground (large shingle and boulders) according to level; they are Bingle, six feot apart, boxed in, and three of them support each capsill. The tressoling is of the lightest description, and merely useful for bracing only, as the weight of the bridge is supported entirely by the tubes. The bays are 20 feet each ; the total length of bridge 1230 yards ; its width 12 feet. Of course, by doubling thetubes, by inserting intermediate tressels, and by trusting, the bridge may bo stiffened to almost any extent, 'but it is supposed that it is sulliciently rigid and strong to meet all present requirements."

According to our contemporary it would seem that the aetjjm of the river on the shingle, far from disturbing the hold of the pipes on their bed, positively strengthens them by building up on the lower side of each pile a natural abutment calculated to resist the greatest force of the stream. If this should prove to bo the invariable consequence of driving each row of pipes, it is difficult to see what danger is to be apprehended from the heaviest freshes. Piles formed of one or more of these gas pipes will always present the smallest possible surface of resistance to the stream, and, when backed up by naturally formed shingle beds, may be depended upon as being absolutely safe. On West Coast rivers, it is true, there would be the risks of contact with floating timber—a consideration which does not apply in such cases as that of the Hakaia—but the passage of timber would certainly not be so seriously interfered with by narrow iron tubes as it would be by heavy wooden structures. As is remarked by the Times, though it may perhaps be considered premature by cautious people to assert that the experiment now in course of solution is a proved success, it will be admitted that enough has been done to rouse the earnest attention both of the Government and the public. ■